Bituminous coating compositions and processes



Patented May 1, 1945 BITUMINOUS COATING COMPOSITIONS AND PROCESSES Bruce Weetman, Glenham,

Agnew, Beacon, N. Y slgnments, to The T and Robert Jamieson asslgnors, by mesne asexas Company, New York,

N. Y., a corporation of Delaware N Drawing. Application August 15, 1941,

Serial No. 407,070

Claims: Our invention relates to bituminous coatin rial and the ag regate.

It is well known that mineral aggregates, and especially past a number of expedients, such asthe use of adhesion improving agents, have been suggested for overcoming these difficulties, but none of these obviously undesirable for road mixing operaleast partially water-soluble. accordance with our preferred method of operawater-soluble adhesion improving agents. How'- ever, t, e greatest diiiiculties in respect to lack of adhesion are encountered in bituminous paving materials for the coating of mineral aggreadhesion improving properties when used in conis required s and water-soluble gates, and our invention will be described with particular reference to such compositions.

I Any surface active compound which is oilsoluble and at least partially water-soluble may be employed in our present invention. As used herein, the term soluble is to be construed as 'meaning easily and completely dispersible in the concentration employed, as well as truly soluble. Any emulsifying agent, wetting agent, detergent, or the like, having the specified solubilities has junction with a polyvalent have found that emulsifying agents of the class comprising oil-soluble soaps of high molecular weight acids and mono-valent bases are particularly suitable for this purpose. As examples of this type of emulsifying agent there may be mentioned the oil-soluble alkali metal mahogany sulfonates and the amine and hydroxyamine soaps of the higher fatty acids. For economic reasons, we generally prefer to employ oil-soluble mahogany sulfonates, such as the alkali metal, ammonium, and substituted ammonium soaps of mahogany sulfonic acids. The sodium mahogany sulfonates, which are readily available commercially, are very satisfactory for our process, and we have successfully used commercial materials having sodium sulfonate concentrations ranging from 27% to '75%.

The optimum amount of water-soluble surface active compound for any particular application will vary to some extent depending upon the nature of the aggregate to be coated and the amount'of water present on the surface of the aggregate. Generally, a higher concentration of such compound is required for the successful coating of igneous and siliceous aggregates than for coating calcareous aggregates. It is also generally desirable to employ'a somewhat higher concentration for the coating of very wet aggregates than is used for coating aggregates which are dry or only. slightly moist. Concentrations of surface active compound ranging from 0.1% .to 2.0%, based on the weight of the bitumetal soap, but we minous material, will usually be found to besatisfactory, and we from 0.5% to 1.0%.

The oil-soluble and water-soluble surface ac tive compound may be used in conjunction with any of the oil-soluble, water-insoluble polyvalent metal soaps of high molecular weight acids, such as thehigher fatty acids, oxidized paraffin wax acids, rosin acids, naphthenic acids, sulfonic acids, and the like. Soaps of acids containing at generally prefer to employ least 12 carbon atoms are most desirable for this purpose. Any oil-soluble, water-insoluble polyvalent metal soaps of such acid maybe used, as for example, the lead, zinc, iron, copper, calcium, and aluminum soaps. We generally prefer, however, to use the lead, zinc, and iron soaps, and

- 140-400 naphtha particularly these soaps of high molecular weight acids derived from the oxidation of petroleum hydrocarbons. Suitable soaps of the lattertype are described in copending application Serial was applied at a temperature ofapproximately 120 F. by stirring with the aggregate for one minute.

Additional samples of the moistened aggregates No. 407,067, referred to above. 5 were coated with an asphalt cut-back of the The 'optimum amount of polyvalent metal soap same composition containing 0.5% by weight of for any particular application will vary to some sodium mahogany sulfonate and 2% by weight extent with the nature of the aggregate and the of an oxidized wax zinc soap. The mahogany amount of water on the aggregate in'the same sulfonate comprised a commercial material of manner as the optimum amount of the waterapproximately 65% sodium sulfonate content soluble surface active compound varies, as pointwhich was easily and completely dispersible in ed out above. Usually, however, from 0.5% to both-oil and water. The soap was prepared by 5.0% of the polyvalent metal soap, based on the double decomposition of an oxidized wax sodium weight of the bituminous material, will be satsoap by means of a water-soluble zinc salt. The isfactory, and we generally prefer to use from oxidized wax, which was obtained by oxidizing 1% t 3% f soap, parafiln wax at a temperature of 250 F. with air Both the water-soluble surface active comat the rate of three cubic et p hour Pe pound and the water-insoluble polyvalent metal p und of wax, in h pr s n e of manganese soap are preferably incorporated directly in the naphthenate as a cataly had a ap fi t n bituminous material, and it is by this means that number 194, and contained 33% unsap the greatest advantages of our process are seat cured. However, it is apparent that various Further sa ples of the moistened aggregates modifications of this procedure could be used, as were coated with an asphalt cut-back of the same for example, pretreating the aggregate with either o p Containing y Weight of or both the water-soluble surface active comd mahogany o ate together with 2% pound and the polyvalent metal soap. For such y ight of the oxidized wax zinc soappretreatment a solvent, such as kerosene or a n eac C e t e P t of t e area f t e very light bituminous surfacing material, could aggregate coated by the bituminous materialwas advantageously be employed t secure adequate visually estimated, after which the coated madistribution of the treating agents. I Either in terials were subjected to a curing Period of 43 such pretreating processes or in employing bituhours at a temperature of 160 F. minous material containing both of the adhesion After curing, the coated aggregates were subimproving agents, standard coating procedures jected to the Nicholson stripping test (Proceedmay be employed, and the bitumen may be usedings of the Association of Asphalt Paving Techin any of the conventional forms, such as molten 5 nologists, January 1932, page 43). This test was bitumen, bitumen cut-back with naphtha, and modified by adding an additional test period at the like. Our adhesion improving agents are 140 F. and by estimating the percent of the adapted for use in conjunction with all types of area of the aggregate exposed by stripping at the coating operations, including plant mixing, stock end of each test period. piling, road mixing, and surface treating. The percent initialcoating and the percent Our invention may be further illustrated by the stripped after each test period in the stripping following specific examples: test are shown in the table below:

gg ggg Mahogany Per cent l c i v e a fi g Aggregate soap, per gg g g initial gg cut-back coatmg F. F. F. F. 80 so 100 120 140 Wisconsin gravel 0.0 0.0 45 33 15 00 05 Do 2.0 0.5 75 5 5 10 25 05 130;. 20 1.0 05 5 5 10 20 45 Tra rock 0.0 0.0 35 15 20 a5 45 1 70 0--- 2.0 0.5 70 a a s 10 15 Do a0 1.0 05 a a 3 s 3 Virginia granite 0.0 0.0 as a 15 25 35 05 Do 2.0 0.5 05 s as s 10 .Do 2.0 11.0 05 a s 5 s 10 Example 1 Example II Dry' aggregates were mixed with 2% by weight of water. and samples of the resulting wet aggregates were coated with 4% by weight of anasphalt cut-back, comprising 73% of an airlblown asphalt of 65-70 penetration and 27% of distillate. The cut-back had a 122 F. Saybolt Furol viscosity of 340 seconds The procedure of Example I was followed, utilizing 5% of cut-back, based on the weight of the aggregate, and 3% of oxidized wax zinc soap together with 1% of sodium mahogany'sulfonate, based on the weight of the cut-back. The percent initial coating and the stripping test results and are shown in the table below:

oxidized Per cant I ripped after I m zinc mig t? Per cent suceessiv test periods Aggregate soup. per per cent initial 0.0 0.0 20 20 50 70 so 00 3. 0 l. 0 95 3 3 3 3 8 0.0 0.0 25 20 30 60 60 80 3. 0 1. 0 95 3 3 3 3 3 Example 111 gather with 1% of triethanolamine oleate, based The procedure o1 Example I was'rollowed, uti- 9 the wetght the t t The percent lizin 47 of cutmack based on the weight of initial coating and the stripping test results are g o shown in the table below:

Percent stripped after succes- Tnethanol- Zinc soap amine Percent swe test periods Aggregate percent of oleate, perinitial rut-back cent ei coating on ,F. .,F F; F

Whack so 100 120 140 Rhyolite 0.0 0.0 25 a0 1 50 10 9o 90 Virginia gramte 0.0 0.0 85 8 10 30 40 60 Do 3.0 1.0 100 a a s 10 10 the aggregate, and 1% by weight of lead naph- Example VI thenate together with 18 sodium mahogany sulfonate, based on the weight of the cut-back. The percent initial coating and the stripping" test results are shown in the tablebelow:

- The procedure of Example I was followed, using 5% of cut-back based on theweight of the aggregate, 2% of oxidized wax zinc soap, in the L ad M h \Per t pir i B a ogany SUGCBSSIVB 8S 0 S Aggregate naphtheziate, sulfona te} 23 8 2 e1 0911 0 er cen O out-back ent-back mating F. O F. F. F. F. 80 so 100 120 140 0.0 0.0 35 15 20 35 45 70 1.0 1.0 10 a s 10 O. 0 O. O 85 3 15 1.0 1.0 05 s s s 20 a5- Ewample IV vform of a 67% solution in kerosene, based on the weight of the cut-back, and 0.5% of the mono- The p ced of Example I was followed, usamyl amine soap of the same oxidized wax, based ing 5% of cut-back, based on' the weight of the on the weight of thecut-back. The percent inaggregate, and 3% of zinc oleate together withitial coating, and the results of the stripping. 1 of sodium mahogany sulfonate, based on the tests are shown in the table below:

Percent stripped after succes Zinc soap, Amine soap, Percent SW6 test penods Aggregate percent of percent or initial cut-back cut-back coating OR OR a F OR OR 1 so so 100 120 140 0.0 0.0 45 15 25 30 45 2.0 0.5 as 3 s 10 10 15 0.0 0.0 45 10 2s 30 45 v 65 i 2.0 0.5 a a 3 a a .weight of the cut-back. The percent initial coat- Example ing and the stripping test results are shown'in The procedure of Example I was followed usthe table below:

Per centstripped after Zinc Gleam, Mahogany Per cent successive test periods Ag egate Per cent of gg ggga initial cutback cut-back. Ming 1* F. F. F. o F. F. 30 Wisconsin graveL. 0. 0 I O. 0 25- 3b 50 70 90 9O 3.0 1.0 85 3 8 15 3O 40 Trap rock.. 0. 0 0. 0 25 20 30 60 60 80 D0 3. 0 I 1. 0 3 10 15 10 1 W9 V 1 aggregate, and 3% of oxidized wax zinc soap to- The procedure of Example I was followed, us-

gether with 1% of the 3-amino-4-heptanol soap of the same oxidized wax, based on the weight or the cut-back. The percent initial coating and ing 5% of cut-back, based on the weight of the aggregate, and 3% of oxidized wax zinc scan toaemou 3 the stripping test results are shown in the table soluble, in an amoimt ranging from 0.2-2.0% by below: weight of said bitumen.

3 4 Percent is tritppted aitedrg succeszinc fi t 1 P out a W as perm Aggregam percent of soa :r ent cg in oi cil -back E W. T. F. "r. F.'

so so 100 120 140 0.0 0.0 45 25 so s5 s5 75 -s.0 1.0 85 a s s s s 0.0 0.0 45 15 35 3.0 1.0, 85 s 5 Va 1 15' Example VIII 2. An asphaltic coatin composition contain- 15 ing an asphaltic coating material, an oil-soluble,

The procedure of Example I was followed, us-. ing 5% of cut-back, based on the weight of the aggregate, and 3% of oxidized wax zinc soap together with 1% of a wetting agent comprising a highmolecular weight oxazoline stearate, based on the weight of the cut-back. The percent initial coating and the stripping test results are water-insoluble polyvalent metal soap of a high molecular weight acid in an amount ranging from 0.5% to 5.0% of' the weight of said asphaltic coating material, and an emulsifying agent which is oil-soluble and at least partially water-soluble in an amount ranging from 0.1% to 2.0% of the shown in the table below: weight of said asphaltic coating material.

Percent stripped alter succeszinc Soap, wr l tt gr Per 0pm sive test periods Aggregate percent of f initial cut-back g coating 0F. o o o o 80 80 100 120 140 Wisconsin ave] 10 0,0 25 50 70 90 90 gr 3. 0 1. 0 75 3 3 3 3 8 0.0 0.0 85 8 10 30 40 60 3.0 1.0 100 3 3 a s s As may be seen from the above examples, the use of oil-soluble and at least partially watersoluble surface active compounds, in conjunction with oil-soluble, water-insoluble polyvalent metal soaps of high molecular weight acids, results in very marked improvement both in the initial coating of wet aggregates, and in the resistance of the coated aggregates to water stripping. In the coating of dry aggregates, similar improvement in stripping resistance is obtained by the use of these materials, but improvement in initial coating .is usually unnecessary in this case.

It is to be understood, of course, that these examples are merely illustrative and do not limit the scope of our invention. We have observed similar improvements iricoating and stripping resistance when coating various other kinds of aggregates and when employing water-soluble surface active compounds and water-insoluble polyvalent metal soaps other than the specific compounds of the above examples. Our adhesion improving agents are also useful in all types of bituminous coating compositions, as well as the particular paving compositions of these examples.

' It is to be understood that the substitution of other types of bituminous compositions and other water-soluble surface active compounds and water-insoluble polyvalent metal soaps, and the use of any other equivalents and-modifications of are inprocedure which would naturally occur to one ing bitumen and an oil-soluble, water-insoluble polyvalent metal soap of a high molecular weight 3. An asphaltic coating composition comprising an asphalt cut-back, an oil-soluble, water-insoluble polyvalent metal soap of high molecular weight acids derived from the oxidationof petroleum hydrocarbons, in an amount ranging from 0.5% to 5.0% of the weight of said asphalt cutback, and an oil-soluble soap of a high molecular weight acid and a monovalent base in an amount ranging from 0.1% t 2.0% of the weightof said asphalt cut-back.

'4. The composition of claim 3 in which the polyvalent metal soap is an oil-soluble, waterinsoluble polyvalent metal soap of oxidized paraffin wax, and the emulsifying agent is an oil-.

agent is an oil-soluble sodium mahogany sulfonate.

A 7. A process for coating mineral aggregate which comprises coating said aggregate with a liquid bituminous material in the presence of 0.5-5.0% of an oil-soluble, water-insoluble polyvalen't metal soap of a high molecular weight acid and0.1-2.0% of 'a surface active compound which is oil-soluble and at least, partially water-soluble,

in the coating of said aggregate.

8. .A process for coating mineral aggregate which comprises coating said aggregate with a liquid asphaltic coating composition in the presence oi 0.5-5.0% of an oil-soluble, water-insoluble polyvalent metal soap of a high molecular weight 4 acid and 0.1-2.0%

' asphalt, coating of an emulsifying agent which is oil-soluble and at least partially water-soluble, said proportionate ranges being base upon the amount of said liquid asphaltic coating composition used in the coating of said aggregate.

9. The process of claim 8 inwhich the polyvalent metal soap is an oil-soluble, water-insoluble soap of high molecular weight acids derived from the oxidation .of petroleum hydrocarbons, and the emulsifying agent is an oil-soluble soap of a high molecular weight acid and a monovalent base. a

10. A process for coating mineral aggregate which comprises applying to said aggregate an composition comprising an asphalt cut-back, an oil-soluble, Water-insoluble polyvalent metal soap of a high molecular weight acid in an amount ranging from 0.5% to 5.0% of the weight of said asphalt cut-back, and an emulsifying agent which is oil-soluble and at least partially water-soluble ng from 0.1% to 2.0% phalt cut-back.

in an amount rangof the weight of said as- 11. The process of claim 10 in which the poly- I valent metal soap is an oil-soluble, water-insoluhle soap of high molecular weight acids derived from the oxidation of petroleum hydrocarbons, and the emulsifying agent is an oil-soluble soap of said bitumen.

of a high molecular weight acid and a monovalent base.

12. The process of claim 10 in which the polyvalent metal soap is an oil-soluble, water-insoluble polyvalent metal soap of oxidized paraffin wax, and the emulsifying agent is an oil-soluble amine soap of a high molecular weight acid.

. 13. The process of claim 10 in which the polyvalent metal soap is an oil-soluble, water-insoluble polyvalent metal soap of oxidized paraffin wax, and the emulsifying agent is an on-8o1ub1e alkalirnetal soap of a high molecular weight acid.

14. The process of claim 10 in which the polyvalent metal soap is an oil-soluble zinc soap of oxidized paraflin wax, and the emulsifying agent is an oil-soluble sodium mahogany sulfonate.

15. A coated mineral aggregate, comprisingcrushed mineral matter, the which have a coating of bitumen bonded thereto by an oil-soluble, water-insoluble polyvalent metal soap of a high molecular weight acid in an amount ranging from 0.55.0% by weight of said bitumen and a surface active compoundwhich is oil-soluble and at least partially water-soluble, in an amount ranging from 0.1-2.0% by weight BRUCE WEETMAN. ROBERT JAMIESON AGNEW.

individual pieces of r 

